#include "pch.h"
#include "md5.h"

#ifdef _DEBUG
#undef THIS_FILE
static char THIS_FILE[] = __FILE__;
#define new DEBUG_NEW
#endif

#define S11 7
#define S12 12
#define S13 17
#define S14 22
#define S21 5
#define S22 9
#define S23 14
#define S24 20
#define S31 4
#define S32 11
#define S33 16
#define S34 23
#define S41 6
#define S42 10
#define S43 15
#define S44 21


#define F(x, y, z) (((x) & (y)) | ((~x) & (z)))
#define G(x, y, z) (((x) & (z)) | ((y) & (~z)))
#define H(x, y, z) ((x) ^ (y) ^ (z))
#define I(x, y, z) ((y) ^ ((x) | (~z)))


#define ROTATE_LEFT(x, n) (((x) << (n)) | ((x) >> (32-(n))))


#define FF(a, b, c, d, x, s, ac) { \
    (a) += F ((b), (c), (d)) + (x) + (UINT)(ac); \
    (a) = ROTATE_LEFT ((a), (s)); \
    (a) += (b); \
    }
#define GG(a, b, c, d, x, s, ac) { \
    (a) += G ((b), (c), (d)) + (x) + (UINT)(ac); \
    (a) = ROTATE_LEFT ((a), (s)); \
    (a) += (b); \
    }
#define HH(a, b, c, d, x, s, ac) { \
    (a) += H ((b), (c), (d)) + (x) + (UINT)(ac); \
    (a) = ROTATE_LEFT ((a), (s)); \
    (a) += (b); \
    }
#define II(a, b, c, d, x, s, ac) { \
    (a) += I ((b), (c), (d)) + (x) + (UINT)(ac); \
    (a) = ROTATE_LEFT ((a), (s)); \
    (a) += (b); \
    }


//////////////////////////////////////////////////////////////////////
// Construction/Destruction
//////////////////////////////////////////////////////////////////////

CMD5Crypt::CMD5Crypt()
{
	context = new MD5_CTX;
}

CMD5Crypt::~CMD5Crypt()
{
	if (context)
		delete context;
}


void CMD5Crypt::GetMd5String(OUT CString& strMD5,IN char* input,IN int inputlen)
{
	unsigned char digest[16];

	Init();
	Update((unsigned char*)input, (unsigned int)inputlen);
	Final((unsigned char*)digest);

	CString strTemp;
	for (int i = 0; i < 16; i++)
	{
		strTemp.Format(_T("%x"), digest[i]);
		strMD5 += strTemp;
	}
}

VOID CMD5Crypt::GetMd5String(OUT CString& strMD5, IN CString strInput)
{
	int len;
	len = strInput.GetLength();
	GetMd5String(strMD5, (char*)strInput.GetBuffer(len), len);
}

VOID CMD5Crypt::Init()
{
	context->count[0] = context->count[1] = 0;

	context->state[0] = 0x67452301;
	context->state[1] = 0xefcdab89;
	context->state[2] = 0x98badcfe;
	context->state[3] = 0x10325476;
}

VOID CMD5Crypt::Update(unsigned char* input, unsigned int inputLen)
{
	unsigned int i, index, partLen;


	index = (unsigned int)((context->count[0] >> 3) & 0x3F);


	if ((context->count[0] += ((UINT)inputLen << 3))
		< ((UINT)inputLen << 3))
		context->count[1]++;
	context->count[1] += ((UINT)inputLen >> 29);

	partLen = 64 - index;


	if (inputLen >= partLen) {
		memcpy(&context->buffer[index], input, partLen);
		MD5Transform(context->state, context->buffer);

		for (i = partLen; i + 63 < inputLen; i += 64)
			MD5Transform(context->state, &input[i]);

		index = 0;
	}
	else
		i = 0;


	memcpy(&context->buffer[index], &input[i], inputLen - i);
}

VOID CMD5Crypt::Final(UCHAR digest[16])
{
	static unsigned char PADDING[64] = {
		0x80, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
			0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
			0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0
	};

	unsigned char bits[8];
	unsigned int index, padLen;

	Encode(bits, context->count, 8);

	index = (unsigned int)((context->count[0] >> 3) & 0x3f);
	padLen = (index < 56) ? (56 - index) : (120 - index);
	Update(PADDING, padLen);


	Update(bits, 8);
	Encode(digest, context->state, 16);
	memset(context, 0, sizeof(*context));

}

//////////////////////////////////////////////////////////////////////////
//private:
VOID CMD5Crypt::MD5Transform(UINT state[4], UCHAR block[64])
{
	UINT a = state[0], b = state[1], c = state[2], d = state[3], x[16];

	Decode(x, block, 64);


	FF(a, b, c, d, x[0], S11, 0xd76aa478);
	FF(d, a, b, c, x[1], S12, 0xe8c7b756);
	FF(c, d, a, b, x[2], S13, 0x242070db);
	FF(b, c, d, a, x[3], S14, 0xc1bdceee);
	FF(a, b, c, d, x[4], S11, 0xf57c0faf);
	FF(d, a, b, c, x[5], S12, 0x4787c62a);
	FF(c, d, a, b, x[6], S13, 0xa8304613);
	FF(b, c, d, a, x[7], S14, 0xfd469501);
	FF(a, b, c, d, x[8], S11, 0x698098d8);
	FF(d, a, b, c, x[9], S12, 0x8b44f7af);
	FF(c, d, a, b, x[10], S13, 0xffff5bb1);
	FF(b, c, d, a, x[11], S14, 0x895cd7be);
	FF(a, b, c, d, x[12], S11, 0x6b901122);
	FF(d, a, b, c, x[13], S12, 0xfd987193);
	FF(c, d, a, b, x[14], S13, 0xa679438e);
	FF(b, c, d, a, x[15], S14, 0x49b40821);


	GG(a, b, c, d, x[1], S21, 0xf61e2562);
	GG(d, a, b, c, x[6], S22, 0xc040b340);
	GG(c, d, a, b, x[11], S23, 0x265e5a51);
	GG(b, c, d, a, x[0], S24, 0xe9b6c7aa);
	GG(a, b, c, d, x[5], S21, 0xd62f105d);
	GG(d, a, b, c, x[10], S22, 0x2441453);
	GG(c, d, a, b, x[15], S23, 0xd8a1e681);
	GG(b, c, d, a, x[4], S24, 0xe7d3fbc8);
	GG(a, b, c, d, x[9], S21, 0x21e1cde6);
	GG(d, a, b, c, x[14], S22, 0xc33707d6);
	GG(c, d, a, b, x[3], S23, 0xf4d50d87);

	GG(b, c, d, a, x[8], S24, 0x455a14ed);
	GG(a, b, c, d, x[13], S21, 0xa9e3e905);
	GG(d, a, b, c, x[2], S22, 0xfcefa3f8);
	GG(c, d, a, b, x[7], S23, 0x676f02d9);
	GG(b, c, d, a, x[12], S24, 0x8d2a4c8a);


	HH(a, b, c, d, x[5], S31, 0xfffa3942);
	HH(d, a, b, c, x[8], S32, 0x8771f681);
	HH(c, d, a, b, x[11], S33, 0x6d9d6122);
	HH(b, c, d, a, x[14], S34, 0xfde5380c);
	HH(a, b, c, d, x[1], S31, 0xa4beea44);
	HH(d, a, b, c, x[4], S32, 0x4bdecfa9);
	HH(c, d, a, b, x[7], S33, 0xf6bb4b60);
	HH(b, c, d, a, x[10], S34, 0xbebfbc70);
	HH(a, b, c, d, x[13], S31, 0x289b7ec6);
	HH(d, a, b, c, x[0], S32, 0xeaa127fa);
	HH(c, d, a, b, x[3], S33, 0xd4ef3085);
	HH(b, c, d, a, x[6], S34, 0x4881d05);
	HH(a, b, c, d, x[9], S31, 0xd9d4d039);
	HH(d, a, b, c, x[12], S32, 0xe6db99e5);
	HH(c, d, a, b, x[15], S33, 0x1fa27cf8);
	HH(b, c, d, a, x[2], S34, 0xc4ac5665);


	II(a, b, c, d, x[0], S41, 0xf4292244);
	II(d, a, b, c, x[7], S42, 0x432aff97);
	II(c, d, a, b, x[14], S43, 0xab9423a7);
	II(b, c, d, a, x[5], S44, 0xfc93a039);
	II(a, b, c, d, x[12], S41, 0x655b59c3);
	II(d, a, b, c, x[3], S42, 0x8f0ccc92);
	II(c, d, a, b, x[10], S43, 0xffeff47d);
	II(b, c, d, a, x[1], S44, 0x85845dd1);
	II(a, b, c, d, x[8], S41, 0x6fa87e4f);
	II(d, a, b, c, x[15], S42, 0xfe2ce6e0);
	II(c, d, a, b, x[6], S43, 0xa3014314);
	II(b, c, d, a, x[13], S44, 0x4e0811a1);
	II(a, b, c, d, x[4], S41, 0xf7537e82);
	II(d, a, b, c, x[11], S42, 0xbd3af235);
	II(c, d, a, b, x[2], S43, 0x2ad7d2bb);
	II(b, c, d, a, x[9], S44, 0xeb86d391);

	state[0] += a;
	state[1] += b;
	state[2] += c;
	state[3] += d;


	memset(x, 0, sizeof(x));
}

VOID CMD5Crypt::Encode(UCHAR* output, UINT* input, UINT len)
{
	unsigned int i, j;

	for (i = 0, j = 0; j < len; i++, j += 4) {
		output[j] = (unsigned char)(input[i] & 0xff);
		output[j + 1] = (unsigned char)((input[i] >> 8) & 0xff);
		output[j + 2] = (unsigned char)((input[i] >> 16) & 0xff);
		output[j + 3] = (unsigned char)((input[i] >> 24) & 0xff);
	}
}

VOID CMD5Crypt::Decode(UINT* output, UCHAR* input, UINT len)
{
	unsigned int i, j;

	for (i = 0, j = 0; j < len; i++, j += 4)
		output[i] = ((UINT)input[j]) | (((UINT)input[j + 1]) << 8) |
		(((UINT)input[j + 2]) << 16) | (((UINT)input[j + 3]) << 24);
}
